Davallia trichomanoides Blume var. lorrainii (Hance) Holttum

Family

Davalliaceae

Nomenclature

Davallia trichomanoides Blume var. lorrainii (Hance) Holttum, Rev. Fl. Malaya ed. 1, 2: 361. 1955 [‘1954’]; Holttum, Dansk Bot. Ark. 23: 234. 1965; Seidenf., Nat. Hist. Bull. Siam Soc. 19: 86. 1958; Tagawa & K.Iwats., Fl. Thailand 3: 163. 1985; Nooteboom, Fl. Males., Ser. II, Ferns and Fern Allies 3: 265. 1998; Boonkerd & Pollawatn, Pterid. Thailand: 234. 2000. – Davallia lorrainii Hance, Ann. Sci. Nat. 5: 254. 1866; Bedd., Handb. Ferns Brit. India: 61. 1883; Tardieu & C.Chr., Fl. Indo-Chine 7(2): 106. 1939. – Type: Lorrain 1732 (BM), Peninsular Malaysia, Penang.

Description

Rhizome long creeping, 3–5 mm diam., densely scaly throughout; scales various as noted in the key to the varieties. Stipes stramineous, about 10 cm long. Laminae deltoid or roundly pentagonous, gradually narrowed from base to apex, about 18 cm long and wide, or up to 35 cm long, tripinnate to quadripinnatifid; all pinnae anadromous; basal pinnae the largest, gradually narrowed from base to acute apex, normally 10 by 6 cm, shortly stalked; upper pinnae gradually smaller upwards; pinnules subsessile or larger ones very shortly stalked, moderately acute to acute at apex, cuneate at base; secondary pinnules sessile, round to moderately acute at apex, cuneate at base, lobed at margin; lobes acute at apex, subcoriaceous, glabrescent, green, paler beneath; veins pinnate, hardly distinct. Sori terminal on veinlets; indusia cup-shaped, up to 2 mm long, 0.7 mm diam.

There are two distinct varieties which are sometimes treated as species. As noted by Holttum (1955 [‘1954’]), the rhizome scales of var. trichomanoides are somewhat variable in colour and hairiness, though those of var. lorrainii are stable and discriminative by themselves.

Key to the varieties in Thailand

1. Scales gradually narrowing from peltate base to acuminate apex, bright brown, entire and nearly glabrous to short-hairy at margin. Ultimate segments lobed more than half-way towards midribs.   a. var. trichomanoides
1. Scales abruptly narrowing above the base to form long tails, dark except for those on young rhizome, with long paler hairs at margin; hairs longer than the breadth of scales, ultimate segments very shallowly lobed .  b. var. lorrainii

Distribution in Thailand

NORTHERN: Chiang Mai, Chiang Rai, Lamphun, Lampang, Tak, Phitsanulok; NORTH-EASTERN: Loei; EASTERN: Nakhon Ratchasima; SOUTH-WESTERN: Kanchanaburi; CENTRAL: Nakhon Nayok; SOUTH-EASTERN: Chon Buri, Rayong, Chanthaburi, Trat; PENINSULAR: Surat Thani, Nakhon Si Thammarat.

Distribution in Cambodia

Kampot, Koh Kong, Kompong Speu, Mondulkiri.

Wider Distribution

Central Burma, Indochina and throughout Malesia.

Ecology

Ecology.– On mossy rocks or bases of tree trunks in light shade to dense evergreen forests at 800–1400 m alt.

Proposed IUCN Conservation Assessment

Least Concern (LC). This variety is widespread and not under any known threat.

Voucher specimens - Thailand

Middleton et al. 5068, Phitsanulok, Phu Hin Rong Kla National Park (E).

Voucher specimens - Cambodia

Long et al. CL113, Kampot, Bokor National Park (P); Poilane 380, Kampot, Mts Elephant (P); Viboth R5-42, Koh Kong, Thma Baing (P);  Pierre 5775, Kompong Speu (P); Long et al. CL425 & CL477, Mondulkiri (P).

Habit on rocks

Habit on rocks

Habit on tree

Habit on tree

Habit

Habit

Rhizome

Rhizome

Rhizome scales

Rhizome scales

Growing tip of rhizome

Growing tip of rhizome

Basal pinnae

Basal pinnae

Upper surface of lamina

Upper surface of lamina

Lower surface of lamina

Lower surface of lamina

Lower surface of lamina with sori

Lower surface of lamina with sori

Sori

Sori

Young sori

Young sori

Site hosted by the Royal Botanic Garden Edinburgh. Content managed by Stuart Lindsay, Gardens by the Bay, Singapore and David Middleton, Singapore Botanic Gardens. Last updated 16 November 2016.